<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <script src="./lib/vue-2.4.0.js"></script>

    <style>
        .ball {
            width: 15px;
            height: 15px;
            background-color: pink;
            border-radius: 50%;
        }
    </style>

</head>

<body>
    <div id="app">
        <input type="button" value="加入购物车" @click="flag=!flag">
        <transition @before-enter="beforeEnter" @enter="enter" @after-enter="afterEnter">
            <div class="ball" v-show="flag"></div>
        </transition>
    </div>
</body>
<script>
    var vm = new Vue({
        el: '#app',
        data: {
            flag: false
        },
        methods: {
            beforeEnter(el) {
                el.style.transform = 'translate(0, 0)';
            },
            enter(el, done) {
                el.offsetWidth;
                el.style.transform = 'translate(150px,450px)';
                el.style.transition = 'all 1s ease'
                done()
            },
            afterEnter() {
                this.flag = !this.flag;
            }
        }
    })
</script>

</html>